Chapter 2

Question 1

Which usermod option should you use to add a user to group?

Answer 1

-G

Question 2

What information is usually provided to the -c option of useradd?

Answer 2

the user’s full name

Question 3

How many secondary groups can a user be in?

Answer 3

up to 31

Question 4

How many primary groups can a user be in?

Answer 4

exactly 1

Question 5

What is Red Hat Enterprise Linux’s default login shell for human users?

Answer 5

/bin/bash

Question 6

When new users are added with useradd, suppose you want them to each get their own copy of the file named .blog.prefs. Where should you put the master copy?

Answer 6

/etc/skel

Question 7

Which options to usermod do you use (1) to lock a user out, and (2) to allow them access again?

Answer 7

(1) -L and (2) -U

Question 8

What’s the problem with changing a user’s userid with usermod?

Answer 8

the user may own some files whose userid is not fixed

Question 9

What’s wrong with this /etc/passwd line? bob:x:543:music:bob:/home/bob:/bin/bash

Answer 9

music is not an integer

Question 10

What’s the best reason for using -u with useradd?

Answer 10

making a system user with a specific userid

Question 11

What’s really wrong with this command? usermod -g wheel -G math,science -c Beverly Wong bev90210

Answer 11

Beverly Wong should be in quotation marks